'use strict';

function even_to_letter(collection) {

  //在这里写入代码
  let arr=[];
  for(let m of collection)
  {
    if(m%2===0)
    {
      arr.push(m);
    }
  }
  
  let result = arr.map(function(i){
    return String.fromCharCode(i+96);
     });
  return result;

}

module.exports = even_to_letter;
